From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38BC3C4332F for ; Wed, 9 Mar 2022 10:35:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230355AbiCIKgR (ORCPT ); Wed, 9 Mar 2022 05:36:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229953AbiCIKgQ (ORCPT ); Wed, 9 Mar 2022 05:36:16 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 34EABEA34C for ; Wed, 9 Mar 2022 02:35:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646822117; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=92tkil4B/YfMjsRlwMuANtc0Vrgq6z66WglTSkkwlNA=; b=OtAHwAOoLqNwbQ7yQBXKYmF/bH9ncCmQXrrkP8okVnQWzuCq4+1b7IfkqNZvkL8XSHDMNL gG+zwWKS0+GXWUJ3sOHY2rvZ6RrPzvm2vlDNymy/DNRBwMPaCxtmu6gQrFvVeG48IirSl3 KAfeHhgAPIqkDTbE64fXz0sM+rluzzo= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-45-SyOOxvSHPAmPA-9z1Q9T1Q-1; Wed, 09 Mar 2022 05:35:16 -0500 X-MC-Unique: SyOOxvSHPAmPA-9z1Q9T1Q-1 Received: by mail-ed1-f71.google.com with SMTP id co2-20020a0564020c0200b00415f9fa6ca8so1061895edb.6 for ; Wed, 09 Mar 2022 02:35:16 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version:content-transfer-encoding; bh=92tkil4B/YfMjsRlwMuANtc0Vrgq6z66WglTSkkwlNA=; b=za2YDij3Oy1sVVXr31lQu1VoS39Pz6JCOtJ8C5FjNlH4ibl1RQUAKg66sDCXo5WhsQ uZ0FVvZ1sveK1jX6qJ9Np/QpLBM0F/qju2n/jtfzDqbDJhK96XlDSj59KgeSq4z7Ezm1 0FNp1j3FLA7EfDKzA2sjzqbezAP9168Z04np2FF3E5UzQzF+1KZQvDqo9zdz1zbYvOvl i3zxcXGv+OoI38ADT5a3onHCXACsYjHFHi38zbFEtT96uvoFkTb2GO1p1+VOigvIufRZ rIEG4wq4/61OlvFzWfpkwcyINceuj974m4WfXrpTmHpzG4wNE0i+dtlgIjpVzsWLlvG/ xwMA== X-Gm-Message-State: AOAM532xENnG9U3TZVlaEDpX141iM7iIswVe/zLwlkJe7fsReJZdnISZ dnGdI9TEjpRuOQTIfvua5GMazQnJA0LATA+IB55HoilkseVxCFsH4aV0XLbxyEZKFZflrWC2nbr tmbzSznvRSLe6q/dY X-Received: by 2002:a17:906:b50:b0:6d6:e503:131c with SMTP id v16-20020a1709060b5000b006d6e503131cmr16974944ejg.597.1646822114619; Wed, 09 Mar 2022 02:35:14 -0800 (PST) X-Google-Smtp-Source: ABdhPJwAPWJSjo0iYiBtPlfXi30N80hLtsRGajYqQqdLwzPHV7Uo+j8kWTXXkYw1BdTVNR4RbtXXtA== X-Received: by 2002:a17:906:b50:b0:6d6:e503:131c with SMTP id v16-20020a1709060b5000b006d6e503131cmr16974912ejg.597.1646822114188; Wed, 09 Mar 2022 02:35:14 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk ([45.145.92.2]) by smtp.gmail.com with ESMTPSA id fy1-20020a1709069f0100b006d229ed7f30sm570156ejc.39.2022.03.09.02.35.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Mar 2022 02:35:13 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id ECC3E192A9F; Wed, 9 Mar 2022 11:35:12 +0100 (CET) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Martin KaFai Lau Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Song Liu , Yonghong Song , John Fastabend , KP Singh , "David S. Miller" , Jakub Kicinski , Jesper Dangaard Brouer , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH bpf-next v10 1/5] bpf: Add "live packet" mode for XDP in BPF_PROG_RUN In-Reply-To: <20220309061018.wn5tddiguywdeyra@kafai-mbp.dhcp.thefacebook.com> References: <20220308145801.46256-1-toke@redhat.com> <20220308145801.46256-2-toke@redhat.com> <20220309061018.wn5tddiguywdeyra@kafai-mbp.dhcp.thefacebook.com> X-Clacks-Overhead: GNU Terry Pratchett Date: Wed, 09 Mar 2022 11:35:12 +0100 Message-ID: <87h787wh0f.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Martin KaFai Lau writes: > On Tue, Mar 08, 2022 at 03:57:57PM +0100, Toke H=C3=B8iland-J=C3=B8rgense= n wrote: >> +static int xdp_test_run_batch(struct xdp_test_data *xdp, struct bpf_pro= g *prog, >> + u32 repeat) >> +{ >> + struct bpf_redirect_info *ri =3D this_cpu_ptr(&bpf_redirect_info); >> + int err =3D 0, act, ret, i, nframes =3D 0, batch_sz; >> + struct xdp_frame **frames =3D xdp->frames; >> + struct xdp_page_head *head; >> + struct xdp_frame *frm; >> + bool redirect =3D false; >> + struct xdp_buff *ctx; >> + struct page *page; >> + >> + batch_sz =3D min_t(u32, repeat, xdp->batch_size); >> + >> + local_bh_disable(); >> + xdp_set_return_frame_no_direct(); >> + >> + for (i =3D 0; i < batch_sz; i++) { >> + page =3D page_pool_dev_alloc_pages(xdp->pp); >> + if (!page) { >> + err =3D -ENOMEM; >> + goto out; >> + } >> + >> + head =3D phys_to_virt(page_to_phys(page)); >> + reset_ctx(head); >> + ctx =3D &head->ctx; >> + frm =3D &head->frm; >> + xdp->frame_cnt++; >> + >> + act =3D bpf_prog_run_xdp(prog, ctx); >> + >> + /* if program changed pkt bounds we need to update the xdp_frame */ >> + if (unlikely(ctx_was_changed(head))) { >> + ret =3D xdp_update_frame_from_buff(ctx, frm); >> + if (ret) { >> + xdp_return_buff(ctx); >> + continue; >> + } >> + } >> + >> + switch (act) { >> + case XDP_TX: >> + /* we can't do a real XDP_TX since we're not in the >> + * driver, so turn it into a REDIRECT back to the same >> + * index >> + */ >> + ri->tgt_index =3D xdp->dev->ifindex; >> + ri->map_id =3D INT_MAX; >> + ri->map_type =3D BPF_MAP_TYPE_UNSPEC; >> + fallthrough; >> + case XDP_REDIRECT: >> + redirect =3D true; >> + ret =3D xdp_do_redirect_frame(xdp->dev, ctx, frm, prog); >> + if (ret) >> + xdp_return_buff(ctx); >> + break; >> + case XDP_PASS: >> + frames[nframes++] =3D frm; >> + break; >> + default: >> + bpf_warn_invalid_xdp_action(NULL, prog, act); >> + fallthrough; >> + case XDP_DROP: >> + xdp_return_buff(ctx); >> + break; >> + } >> + } >> + >> +out: >> + if (redirect) >> + xdp_do_flush(); >> + if (nframes) >> + err =3D xdp_recv_frames(frames, nframes, xdp->skbs, xdp->dev); > This may overwrite the -ENOMEM with 0. Argh, oops! And here I thought I was being clever by getting rid of the indirection through 'ret'. Will fix, thanks! -Toke